To my knowledge, WINE doesn't interpret filesystems (FAT32, ext3, NTFS, HFS+, etc.), or is even filesystem-aware. But that shouldn't matter if your operating system is able to interpret a filesystem for it. If you can get your operating system to mount what it is you want WINE to use to a folder, you can go into winecfg and associate that folder with a drive letter in WINE.
But be careful what you do with it. Don't install a program into Windows and then have WINE run that program off the Windows partition. Only run programs that have been installed by WINE when running programs with WINE. In fact, JUST from a program being on an NTFS partition, that can cause problems with WINE.
To get WINE to see anything, go into winecfg, go to the drives tab, and associate a drive letter with the folder containing what you want WINE to see. Remember that Linux and Mac OS X don't have drive letters. There is only one root directory. In that directory folders can be made, and you can tell the operating system to display the contents of a partition in any folder. So if you want WINE to use a drive, you associate the path to the folder in which the drive's contents are displayed to a drive letter.
So if you want WINE to see in a virtual machine made by VirtualBox, just do a VirtualBox network share, and associate the path to the share folder (as the operating system running WINE sees it).
If you want WINE to access the filesystem more directly, mount the hard drive image (virtual machine must be off...or SHOULD be) to a path (or paths, plural, if there is more than one partition) and associate that path(s) to (a) drive(s) letter(s).
To learn how to mount a vdi, read the sixth post here: http://ubuntuforums.org/showthread.php?t=871367.
Cheers,
Jake